<template>
    <el-menu default-active="1-4-1" class="el-menu-vertical-demo" active-text-color='#ffd04b' text-color='#fff' background-color = '#545c64' @open="handleOpen" @close="handleClose" :collapse="isCollapse">
       <h3>{{isCollapse ? "后台" : "通用后台管理系统"}}</h3>
       <!-- 用v-for渲染noChildren数组 ， 进行数据绑定时注意加上 : 或v-bind: ， -->
       <el-menu-item @click = "clickMenu(item)" v-for="item in noChildren" :index="item.path" :key="item.path">
            <i :class="'el-icon-' + item.icon"></i>
            <span slot="title">{{item.label}}</span>
        </el-menu-item>
       <el-submenu v-for="item in haveChildren" :index="item.path" :key="item.path">
            <!-- 此处返回的item是lable为“其他”的项 -->
            <template slot="title">
                <i :class="'el-icon-' + item.icon"></i>
                <span slot="title">{{item.label}}</span>
            </template>
            <!-- subItem子项，subIndex子索引 指向“其他项”中的子项“children” -->
            <el-menu-item-group v-for="(subItem,subIndex) in item.children" :key="subItem.path">
                <el-menu-item @click = "clickMenu(subItem)" :index="subIndex">{{subItem.label}}</el-menu-item>
            </el-menu-item-group>
        </el-submenu>
    </el-menu>
</template>

<script>
  export default {
    data() {
      return {
        menu:[
                {
                path: '/home',
                name: 'home',
                label: '首页',
                icon: 's-home',
                url: 'home/index'
                },
                {
                path: '/mall',
                name: 'mall',
                label: '商品管理',
                icon: 'video-play',
                url: 'mall/mall.vue'
                },
                {
                path: '/user',
                name: 'user',
                label: '用户管理',
                icon: 'user',
                url: 'user/index'
                },
                {
                label: '其他',
                icon: 'location',
                children: [
                    {
                    path: '/page1',
                    name: 'page1',
                    label: '页面1',
                    icon: 'setting',
                    url: 'other/page1.vue'
                    },
                    {
                    path: '/page2',
                    name: 'page2',
                    label: '页面2',
                    icon: 'setting',
                    url: 'other/page2.vue'
                    }
                    ]
                }
            ]
      };
    },
    methods: {
      handleOpen(key, keyPath) {
        console.log(key, keyPath);
      },
      handleClose(key, keyPath) {
        console.log(key, keyPath);
      },
      //菜单响应
      clickMenu(item){
        this.$router.push({
          name:item.name
        })
        this.$store.commit('selectMenu',item)
      }
    },
    //过滤：分为有无子项两种，返回数组
    computed:{
        noChildren (){
            return this.menu.filter(item => !item.children)
        },
        haveChildren (){
            return this.menu.filter(item => item.children)
        },
        isCollapse(){
          return this.$store.state.tab.isCollapse
        },
        // asyncMenu(){
        //   return this.$store.state.tab.menu
        // }
    }
  }
</script>

<style lang='less' scoped>
  .el-menu-vertical-demo:not(.el-menu--collapse) {
    width: 200px;
    min-height: 400px;
  }
  .el-menu{
    height: 100%;
    border: none;
    h3{
        color: #FFF;
        text-align: center;
        margin: 15px;
    }
  }
  
</style>